Biological and Esthetic Evaluation of Ceramic Onlay With Different Preparation Designs

Aim of study: is to asses biological and esthetical success of ceramic onlay restorations while preparing the teeth using shoulder finish line preparation versus butt joint with bevel preparation. Methods: Patients with need to posterior onlay restoration (premolars and molars) will be allocated into two groups either conventional (shoulder finish line) or conservative group (butt joint with bevel), after tooth preparation impression, restoration fabrication, try in, cementation and restoration will be evaluated two weeks post cementation then follow up will be held every two months for 1 year.